Hi everyone! I'm new to this site, but I'm really excited to see so many others who love doing tricks with their dogs. I use trick books but sometimes find I have to modify things for my particular (stubborn) dog!
Anyways, for the cover your eyes trick I had to do the same thing. It was very difficult trying to get the tape on our puppy's forehead because she always tried to bite it before we could get to her snout or she'd lift her head so we couldn't get it on there.
Anyways, I realized that she covers her face if you blow on her snout. So I started doing that and saying "cover" as she covered her face, then I'd verbally praise her. After a day of doing that I started saying "cover" as the command and then giving her verbal praise, a treat and an enthusiastic pat when she did covered. This literally took 2 days and she has it down!